 When Alexander was arrested by supporters of the imperialist Antipope Victor IV, it was Oddone who freed him and sent to safety in Campania.Oddone took over the military leadership of the city of Rome during the absence of Alexander and even afterwards.His son Leo was captured in battle with the emperor's troops in 1167 and he himself led the largest army of Roman citizens since the days of the Roman Empire into battle at Monte Porzio, where he was defeated by Christian I, Archbishop of Mainz.